Rotary hydraulic torque converter



Se t. 16, 1952 Filed June 24, 1946 D. F. MGGILL 2,610,468

ROTARY HYDRAULIC TORQUE CONVERTER 4 Sheets-Sheet l Q W/E/W'UR DANIEL F. MCGILL' .D. F. M GILL ROTARY HYDRAULIC TORQUE CONVERTER Sgpt. 16, 1952 4 Sheets-Sheet 2 Filed June 24, 1946 ll l AAAQAAQ W EN g 3 g gm was} mi mu 3 g g Sept. 16, 1952 D. F. M ILL 2,610,468

ROTARY HYDRAULIC TORQUE CONVERTER Filed June 24, 1946 4 Sheets-Sheet 3 N U Q DANIEL F-. GILL.

7 TT'U NE W5 Patented Sept. 16, 1952 ROTARY HYDRAULIC TORQUE CONVERTER Daniel F. McGill, Portland, Oregx, assignor to Donald W. Green, trustee, Portland, Oreg.

194s, seria1 No.s78,90 2

Application June 24, azio'i-njms. (c1. Go -54y This invention relates to a power transmission of the type having interacting; hydraulic and gearing components for transmitting torqu irom a driving shaft to a driven shaft in different speed andtorque ratios.

The present transmission is especially-suited to meet flexible power requirements,- andthepreferred embodiment of the invention is designed particularly for automotive use, but this application of the principles of the invention, is to be taken as illustrative rather than as a limitation of the invention. f

In th present transmissionthe power flow may be said to be divided into two parallel but not in- 7 dependent paths between the driving and driven shafts wherein the division of power; between the two paths varies under differentoperating conditions to adjust the over-all torque multiplication and speed ratio to suit thedemands "of those conditions so as to constitute an automatic transmission. The hydraulic component of the transmission comprises three elements which interact with each other through the medium of the hydraulic fluid, and the gearing componentcomprises three interengaging elements, two of which are connected with'two of the fluid driving elements. One of the elements of the fluid driving component is connected with the power input or driving shaft, and a third element in the-gearing component is connected with thepower output or drivenshaft.

Specifically, the hydraulic driving component comprises an impeller, a turbine runner and a reaction member all having vanes in a-common fluid circuit. The gearing component comprises essentially a sun gear, planet gears on a planet carrierand a driven gear on the D9Wr;output shaft. The'sun gear turns with the turbine runner, and the reaction member in the fluid driving component is integral withthe planet carrier whereby'one-path of power flow in the transmission is through the turbinerunner; and sun gear and the other path is through the reaction memberand planet carrier. By virtue otf the interaction between the elements-where :these power flow paths divideand re-'-ur 1ite,on e or the other of these paths may predominate inassuming a major portion of the load and-under certain operating conditions the entire, power flow may be directed exclusively through one of the paths. The variable division of the power flow in this manner occurs in response to external load. and speed conditions and internal operating ch'aralc 'teristics of the fluid driving component automatically to change the over-all driving ratio of the transmission to suit the external conditions of the moment. 1 s 9 This invention relates tol improveni over transmissions of the general type disclosed-in-my men i e i eiiq e Seria N -j} iqtifilifiie October 26, 1943, for Power Transmission Device, now Patent No. 2,465,,739, issued March 29, 1949; and Serial 'Nof5'63,007, filed Novemberll, 19.44, entitled'fPower Transmission System. 7

Improvement of theinternal operating characteristics of Yr the fluid ."drivingi' component c'on-.

stituesone of the-Qprimarylobjects of thepre'sent invention. .'.The' degree of torque multiplication and the eiiiciency of. transmission obtained in this component dependtoa considerable extentupon the fluid flow patterns. produced under different conditions. The nature-of, the flowfpatt'erns throughthe different setso'f vanes andchannels is especially important in a transmission for automotive or-like use because the operating condi-. tionswhich requireapower transmission are'so variable that the p'artscannot bedesigned for any set standardcondi'tions such as may bedone in a steam turbine, for example, operating atia fixed speed under regulated steamlpress'ure'. In stead of compromising the design characteristics in an attempt 'to make the fluid flow pattern substantiallythe same under diverse conditions, the present design recognizes the tendency ofi'the fluid to. change its flow pattern under diiie'rent conditions and provides for and utilizes this change asa contributing rather than a'detrimental'factor in the transmission-and multiplication of torque. Y i v Whereas in most conventional fluid transmission devices the hydraulic fluid iscaus'ed to circulate in a continuoustoroidali'path advancing The fluid driving and gearing components of the transmission are contained within twochambers formed ina housing mounted for'rotation in a stationary casing; An overrunningor oneway engaging brake is provided between thecasing and the housing to prevent reverse rotation of the housing while permitting its forward-rotation under normal forwardidriving' conditions; Within the fluid driving chamber are contained the impeller, reaction member and runner,'h'av ing novel and improved arrangements of vanes for directing-a. fluid circuit through this'ch'amber in different directions under difierentoperatihg conditionsi obtain; "improved --eificiency= and greater multiplicationof torque "than vconventional fluid transmissions; In the gearing chamalignment with the sun gear and the rotating parts of the fluid transmission component.

The reaction member in the fluid transmission component carries two sets of vanes fixedly mounted in the transmission housing. A first setof vanes On the reaction member is of novel design and arrangement, and immediately'surrounds the impeller to receive the entire fluid'output therefrom. Under high torque conditions when the housing is stationary, thevanes in the first set act solely as guide vanes for delivering the fluid flow to a circular channel and then to the vanes of the runner at an advantageous angle of entry. After leaving the runner the fluid flow is next directed through a circular channel into the second set of vanes in the reaction member, from whence it returns through a circular chamnel to the eye of the impeller.

In the impeller the fluid travels radially out wardly as it revolves in a pumping action which produces a high velocity of flow through the various working stages in the fluid circuit. Upon leavin the impeller the fluid can travel in an outward direction no longer, and so it is turned by the housing to move through the guide vanes of the reaction member in an axial direction accompanying its circular motion within the housing. The fluid, thereforey-travels' in a helical path in the first set of vanes in the reaction member, and is moving with a high rotational velocity as it is directed into the vanes of the runner. A wall of the housing reverses the axial movement of the fluid from the guide vanes while facilitating its continuous rotational movement so that the fluid moves into the runner rotating in the same forward direction it has been traveling through the guide vanes but moving axially in the opposite direction as it enters the turbine runner. 0r revolving very slowly, the curved bucket shape of the runner vanes causes the fluid to leave'the runner in a tangential direction opposite to its direction of entry, whereby the fluid is caused to circulate in a reverse direction around the housing. An annular ohamberon the outlet side of the runner receives the fluid in'reverse rotation 1 and causes it to move radially inwardly in a tightening spiral path and then reverses its direction of axial movement as it enters the second set of vanes in the reaction member. These vanes are also of bucket shape, and under the assumed condition of stationary or substantially stationary housing, and stationary or slowly revolving runner, the rotating fluid impinges upon the back sides of the bucket vanes in the reaction member, thereby opposing the tendency in the first set of vanes in the reaction member to cause the housing to rotate in a forward direction. The fluid issues from these vanes stillwith a reverse rotary movement which continues as it returns in a spiral path in a large passageway'leading back: to the eye of the impeller. The impeller vanes are set at an angle toutilize this counter rotation of fluid flow to advantageby'acc'elerating' its radial movement to produce-an unusually high radial velocity of the fluidin starting and under conditions When the runner is stationary v r 4 when maximum torque multiplication is desired Under the operating condition just described, both the gearing component and the second set of reaction vanes producea counter torque on the housing in opposition to forward torque exerted in the first set of vanes in the reaction member. The reaction member then tends to rotate the housingbackwardly, but such rotation is prevented by the overruning brake so that the housing is constrained to remain stationary.

As the description proceeds in connection with the preferred embodiment illustrated in the drawings, it will be noted that the flui is discharged from working stages in each set of vanes through channels in a whirling motion providing an advantageous entrance angle into the next set of vanes. The axial direction of movement of the fluid changes from stagetestage'asthe fluid moves from one set of vanes to the but the parts are so designed that the velocity of rotary movement of the fluid far e"'e'e'ds its velocity in axial or radial 'directiensw ie'rehy these changes indirection do notproduce any appreciable loss in energy in th e sy'stern f, an iin portant feature of the present invention is the unique action which takes place-when the runner reaches a certain critical speedwith respect re the velocity of fluid circulation; noted 7 hereinabove that'when the run er is stationary or rotating very slowly, ito'perates tb 'reverse'the' direction of rotation of the fluid so that the discharge from the runner rotates a "direction" counter to its intake. However; at l'iigherruhner speeds the discharge from the runner-will continue in the 'sam'e'd'irect'ion as at 'entry so as to cause the direction of fluid flow to enter the bucket-vanes of'the reaction memberte exert a torque in a forward direction on the reaction member and transmission housing; Because of the conflnedspace in'the annular passage on the discharge side of the runner; this' fl'ow change takes place abruptly at a certain'critical 's'pee'd converting the reaction merrib'erdnto a driving member. Forward rotation of the housing occurs whenever the forward torque exerted by both sets of vanes in the reaction member-exceeds the reactiontorque exerted upon the housing by the planet gearsiri the gearing component: When thisoocurs the housing leaves the abutment provided by the overrunning brake-,- and rotates in a forward direction at some speed less than that of the runner. I

t is, therefore; a'fuirther. object; of the invention to providea-reactio'n r'r'ieir'ib'e'r a fluid d-r i'v ing component which is constructedand-arranged to function as a driving mem'ber under certain operating conditions- Another object is to providea reaction mem her in a fluiddrivingcomponenthavirig set of vanes arranged diagonally withrespect' to the vanesof an impeller to avoid p wer'ini puises and to receive the'fl'uid discharge from said impeller to exert a guiding influence on: said discharge and, at the same time; to develop torque to coin stitute said reaction memberf-a's an additional driving member under certain operating conditions; J 7

Another object is .to provide" a transmission which will drive as a, fluid coupling in substantially a1 to 1 speed and torque ratio and which will respond to increased load by automatically producing a multiplication oftorquetomeet the additional demands; A

An ther object-is-to' provide a transmission'that will operate-as a torque converter i n starting' or reservoir.

aeiogice when highertorques are required and as acorn binationof fluid coupling and --tor que converter f where lessftorque and morespeed is desired. r

"Another object is to provide a fluid driving component in which there isno radial movement ofthefluidin torque producing members. 1

Anot er object is to provide a fluid tran's'mis siori component having a plurality 1 or sets of torque-producing vanes through which the tra els ingenerally axial directions. -'Another *object to component having an impeller and working'stages' in which the fluid is directed axially and talngem tiallythrough successive 5 working stages, and radially in a spiral' path concentric with the-axis of rotation of the-parts from one 'working stage I tothe next a d from the last working sta gehack into'the eye of the impeller.

'Another object "is to; provide a fluid driving" componenthaving a predominately circular flow ofthefiuid medium in which the direction of flow is abruptlyreversed'undercertain operating con V a rovide a fluid driving ditionstdchange 'a' reaction member in said componnt-to a driving member.

circular, rather than axial; motion.

9 Another object is to provide thetype' described'having a novel overrunning brake to prevent reverse rotation of a member in said-transmission at all times, and capable of locking said-member against rotation in either direction for a reverse drive through said transmission. 51 I 7 j Another-object to provide a transmission having a fluid driving chamber and agearing chamber constituting aj reservoir for the fluid driving 'chamber' and novel pump means con nected with a suction tube in the gearing chamber to pumphydraulic fluid fromf'said gearing chamher to saidfluid driving chamber to maintain fluid pressure in the latter chamber under all operat ing; conditions without 1 pumping air from said Another ebject 'is to provide means-in a transmissicu-of-the type "described for locking the parts-in a direct mechanical driving "connection.

These and other objects will be better understood 'as the'desc ription proceeds in connection with the preferred embodiment shown in the accompanying drawings. It is [tobe understood,"

however, that thepresent embodiment is referred to for purpose of illustrating the principles of the invention and notfor the purpose of limiting the -inventionfi Various changes may be made in the 'construction and arrangement and a in the proportions of the various parta'and all such modifications within the" scope of the appended claims are includedin the invention. g V

In the draw ing'si V -Figurej 1 is for the most part a longitudinal sectional view ofthe'present transmission, sh wing t he manner iirwhich it may be used in an automobile' or similar vehicle; certain parts being v shown in elevation. I r

- Figure 2 is a crcss sectional view jthrough the gearingcomponent of the transmission;

Figure 3 'is'a developed view, with parts broken awayfshowing the fluid paths through the'various sets of vanes and passages in the hind driving component, and including a showing of certain of the parts inlongitudinal cross section; .c Figure' li is a crosssectionalview of-the impeller, taken'on' th'1ine4 4 iii-Figure 3;

transmission of Figure 5 is a cross se'ctional view .or the pump mechanism,'taken on the line 5+5 in Figure 1; 1

Figure 6 isa fragmentary lorig'itudinalsectional view through the pump mechanism and including the hydraulic fluid inlet tubes in the earingchamber; .c

Figure l-is a view takenfon'the' line 1-4 of Figure 6, showing thejmounting and'ball check valve at the outer end of'theinlet tube;

Figure 8 is an enlarged fragmentary view showing' the pressure relief valve between the fluid driving chamber and the gearing chamber;

Figure 9 across sectional view takenapproiiimate'ly" on theline' -9 of Figurfe 'l,'fsho wingftheover-running brake mechanism; f i f 7 Figure id is a' frag'mentary'seetiqrial'view show ing"de tails of certain operating 'mechanism associated with the 'overrunning brake; and

Figure ll is anenlarged fragmentary longitudi nal sectional view of the overrunnihg brake and associated mechanism, taken in the same plane shown" in Figure 1.

as Figure lbut includingiri-ternal structure not engine flywheel M enclosed inthe usual station ary casing 15 bolted to the engine block. r'

. 1 General organization l" The present transmission includes, in general, a friction clutch l6 for connecting the fluid impeller with the engine, a dog clutch I! for connecting thetransmission housing with the impeller, a transmission unit l8,, and an overrunning or one-way engaging brake mechanism I9. Thetransmission unit [8 comprises a housing 20 rotatably mounted within a stationary casing 21 which isbolted to the flywheel casing l5: As will be hereinafter pointed out in connection with the description of the overrunning brake l9, its function is tq prevent reverse rotation of the housing Ell-with-respect to the direction of rotation of the engine, while permitting its forward rotation at such times as the vehicle is intended to operate in a forward direction. Means are also providedin the overrunning brake for locking the housing 20 against'rotation in either direction when elements in the transmission are shifted intoa reverse gear toicause the driven shaft to operate in a'reverse-direction. vThe transmission unit l8 further. comprises a fluid driving component22 contained within a' fluid driving chamber 23, and a gearing component 24 contained within a gearing chamber 25, wherein the two chambers23 'and'25 arearr'anged in end to end relationon'opposite sides of a transverse wall 26 in the housing 29. The fluid: driving encl of the transmission unit, as illustrated, has a e' present transmission" is illustrated in Fig nesting-the transmissionunit l8v from the engine; The engine crank shaftterminates ina flange 3! to which the flywheel l4 issecured by means of bolts 32. A shortpower input shaft 33 has an inner end extending into the fluid,

driving chamber 23 supported in a bearing; 34 and in a pilot bearing ina-manner'which will presently be described; andan outerend carrying a circular plate;3'| within the rim of the fly:-

wheel. The plate 31 is;fiXedly secured on this shaft by means-of a key 38 and a nut 39. Within the rim of the flywheel a plurality of 'arcuateclutch shoes-40 are mounted for; radial movement on the plate 31, this 'movement abeing produced by the toggle action of a plurality of levers 4]. The levers 4| have short .bell crankarms-M terminating in ball ends 43"fulcrumedin bush--- ings 44 in the plate 31, and have eyes 45form ing bearings for pins 46 on the shoes 43 whereby the shoes may bewithdrawn from contact with the flywheel by moving the lower ends 47 of the levers. ferential groove or channel ina sliding-collar 48 on the hub 43 of the flywheel. Springs are provided to act between the plates 3! and'the.

shoes 40 to normally urge the latter into gripping engagement with theflywheel to drive the shaft 33. A shaft 50 mounted in a bracket 5| carries a yoke or finger 52 for moving the collar 43 to the left as viewed in Figure 1 against the spring action to disengage the clutch. The shaft 50 is intended to be connected with the convene ticnal clutch pedal in the vehicle, andmeans may be provided if they are not already v present for locking the pedal in the depressed position to maintain a positive neutralwherein there is no tendency for the shaft l l 'or'any parts within the transmission unit to revolveor creep when the engine is running-and-thevehicle is standing still. V

The housing -20 is supper-ted by end members 58'and 59 for rotation'in-bearings fifl'and El, thebearingtflbeing supportedin a plate 35; at-',- tached'to the flywheelcasing I5 byscrews 36,

and the bearing 6| beingjsupDOrtedin the'rear end of the casing 2I. The previouslymentioned bearing 34 forthe'sha'ft 33 is carried by theend member 58. The end member 58 is provided with internal 'teeth- 62 adapted to engageco mating teeth B3 on a collar-54 which is internally splined for longitudinal sliding movement on splines 35on the shaft 33. Thefcoll'ar -64 mayth'ereb'y beshifted mm and outof *engagement 1 with the teeth 62 by-meansof a fingeror-yoke- 65 on a shaft/6'! mounted in a-bracket'BB: Bothbrackets 5i and 68 are carried bythe mate *3 5;

As shown in Figure 1, the housing'ZU is normally" free of the shaft 33"but may-be positively connected therewith by rotating the shaft 61" by means of a conventionalgear shiftinglever'on the vehicle to engage'th'eteeth GS with'-the teeth 552. With referenceto the transmissiomuhit l8;

the-shaft 33 may "be-regarded as th'e'driving or power input shaftand the-shaft! 1 maybe re-'-- garded the driven or powersoutputrshaftt- Fluid drioingromponent" a greater number of small vanes 14 to exert a pumping action upon the hydraulic fluid to cause -i it. to circulate :at high;- velocity;.-in":a working cir- The lever ends-41 ride in acircumcuitzthrough other sets of vanes in the fluid driv ing .chamber to produce. a torque multiplication in the fluid drivingcomponent of the transmis sion. The arrow indicates the direction'of-rotation of theimpeller'as viewed from theflywheel end ofithe transmission. Under certain operating conditions; which will presently be described, the hydraulic fluidis returned to the eye of the impeller in a counterclockwise circular motion as indicated by the solid arrows 16,- and under otheroperating. conditions ,the fluid enters the eye of the impeller with a clockwise rotation as indicated by the broken line arrowsgl'l. When. the fluidentersin .thedirectionof thearrows J6; therotation of the impeller; and the curvature of the large and small vanes, indicated at 18, changes therotation of the'hydraulic fluid from counterclockwise to clockwise in aihighvelocity dischargehaving radial and tangential components which are .utilized to transmit torque to other sets of vanes mounted for. rotationwithin. the fluid driving chamber. The backward in clination of the vanesor blades 13 receives counterrotating fluid without shock or retardation to I the flow, and the forward curvature at 18 of both the large and small vanes imparts a tangential throw to the fluid as it leaves the tips of the blades. Whenv the fluid enters the'eye ofthe. impeller in the direction shownby the broken line arrows 11, it impinges first upon concaveportions 13 at the inner ends of the large vanes, returning a certain amount of its kinetic energy back to the impeller. Then, as the fluid travels. outwardly between the large and small vanes, the rotation of the impeller and the forward curva ture of the surfaces 18 at the periphery ofthe impeller again cause the fluid to be discharged" at a high velocity having radial and tangential components comprisingin general a continua tion and acceleration of flowin the direction of the arrows IT. Thi modeof operation and theadvantages derived therefrom-will behereinafter discussed in greater detail.

Fixedly secured within the housing 20 is are-- action member 80, preferably provided With pins or the like 8 l, as shown in Figure 1, for transmitting its torque to the end member 58 of 'the-housing- The reaction member contains an outer set of vanes 82 surrounding the impeller and receiving the discharge therefrom, and an inner set of vanes 83 surrounding an inner cylindrical rim 84 defining a central opening or eye 85 havingthe same diameter as the eye of the impeller. A cylindrical rim 86 connects the inner edges of the outer'vanes 82 to define'radially closed pas-,

sages 87 therebetween, and a curved wall 88 connects this rim with the rim 84. The outer ends of the vanes-83 are similarly connected and sup ported, by a cylindrical rim 89defimng radially closed passages 90. The vanes 82 are set diag onally with respect to the impeller-vanes to act as guide vanesto impart a rotational movement to the fluid body and to split the discharge streams from the impeller-in all positionsofthei impeller. The-individual dischargestreams from the impeller are thereby out off gradually; without shock or power impulses as they are diverted from one of the passages 8'! to the next when the impeller is rotating relative to the reaction member 80. Thevanes 82 maybe-slightly curved as,

shown to'enhance a-fluid coupling action which exists betweenrthe impellerand' this particular set of vanes inthe reaction member. The blades 83 may besaid to. be of-bucket shape, being curved to present concave faces- 9ltoi-clockwise's 39 moving fluid and convex faces 92 to counterclockwise moving fluid. These vanes are set in radial positions between the rims 84 and 89 and appear in sideview as shown in full lines in Figure l.

'Thebucket shape of these vanes is best shown in Figure 3, where the rim 89 has been broken awaytoexpose their ends. I w

The front and rear outer faces of the impeller are formed with aligned annular shoulders 93 and Mcarrying a pair of sealing rings 95. The

rings 95 flt'their respective shoulders closely and are spaced apart'bya plurality of pins or struts a 96;causi'ng-themto engage the end member 58 ticn of fluid rotation at the time. Upon leaving the vanes 83 of. the reaction member, the fluid enters into the annular passage I03, where it is free to rotate according" to its directionof motion ina tightening-spiral path until it is in a position topa'ss'through the eye 85 at the entrance 'to}the impeller. It will be understood that the motion of the fluid through the eye as,

" represented by the arrow m in Figure 1, is in and the forward edge'of the rim 84 of the reac:

tion member 80. through the impeller, and suflicient clearance is provided b'etween the front and rear side Walls of the impeller and the rings 45 sothat the latter'have' freedom for limited axial movement on the shoulders 93' and 94. The rim 84' and the endmember 58 are assembled together in rigid precise relationship, and the rings 95 revolve freely"between these members with a minimum 6f friction while floating on the shoulders 93 and B4 toefiect a balanced pressure seal between the -relativelyrotating. parts without producing a drag therebetween. Accommodation is thereby provided for changes in theaxial position of the impeller without destroying the seal or bringing the 'impeller-intocontact with other parts. The

shape: of the'Vanes I05 is shown in Figure 3,

there-be'inga concave face [01 exposed to the clockwis'e' directed fluid flow from the vanes 82. The rear sides of the'vanes l05 are of convex shapeiasindicated atl 08.

'The' Ivariouslsets f vanes just described constitute successive working stages disposed in series'ma fluid circuit leaving the rim of the impeller andfreturning. to the eye of th impeller. The large and-small vanes between the side walls ofthe impellerdeflne passages l I!) through'which thesfluid travels in radial directions as indicated "-ebyithe ar'row H15. in Figure 1. The discharge fromv the impeller is receiveddirectly in the passages aizbetweenthe vanes'82 in which passages eitltrayels? in. a diagonally spiraldirection as it :"movesYaXially in arearward direction towards a circumferentialannularpassage H3 in the housing20. "In theipas'sage N3 the fluid flow spirals inwardly-to a'shiallerradius of rotation an'dthen reverses'its axiallrncver'nent to a forward direction asitinipinges' tangentially upon the concave sides "I lililrefithe bucket vanes I 'ofthe runner, the :3 flow through the runner being indicated generally i loyjthe arrow i l ilinFigure 1. The fluidi's'disf charged fromthe runner into ana'n'nul ar' passage -{l deflned'byfthe curved wall- 88 of the reaction memter Bi); where it may circulate in high speed f'rotation in either a clockwise or counterclockwise direction according to the direction of its" dis- 1 charge from the runner. In. the'annular passage I [5' the rotating fluid crowds inwardly, and then The pins 96 pass loosely reality an advancing motion in a spiral path at a high rotationalyelocity, as though the elethrough the eye 85 is larger than the cross sectional areas of certain of the other passages through which the fluid passes, but this does not result in alower fluid velocity through the eye because the fluid does not travel straight through in an axial direction, but as a mass" whirls around the aXis ina close spiral'to enter theeye of the impeller without end thrust or shock. An important feature and mode of operation in the present arrangement and construction is the maintenance of a uniform high velocity circular flow of the fluid in all parts of the circuit. The various passages are designed to'maintain this circular flow even as the fluid returns back to the impeller, as indicated by the arrows to and T1 in Figure 4. If the passage through the eye 85 were not of increased cross sectional area, a circular-flow therethrough would be impossible withoutaccelerating the fluid at that point, because then thearea of the passage would just handle the volume of fluid in direct flow.

In the fluid circuit through the various vanes and passages it will be observed that the fluid always advances in an axial direction in working stages of the circuit and travels in a spirally radial direction in non-working parts of the cirwCllltbGtWGGll working stages, referring'to the re- .action 'vanes and runner vanes as working stages of the circuitwhere the fluid converts some of its kinetierenergy into torque, and disregarding wardly through the reaction vanes 82 at a constant radius of rotation until it reaches th passage I I3, where its axial movement is temporarily arrested and it is crowded into a smaller'radius of rotation. The annular passage H3 also operates to reverse the axial movement of theliquid to send it back through the runner vanes on pitsnew radius of rotation. In the annular passage N5 the moving mass of fluid again contracts i passing through the reaction member vanes 83.

In th e annular passage Hi3 the revolving fluid is ,crow'dedinto a radius of rotation corresponding by the impeller. This action is facilitated by the formation of smooth curves on the impeller and runner and l fl l in the reaction member, fand runner wall portion .88 and H32, and in the ,wall .of--wth e,housing m-which outlines. the a1inular passage 5 i3.

11 The fluid drivingchamber-23-is sealed-atall joints by a shaft seal I-23 in'the-end-member58, a sealing ringv I c-betweenthe end member 58 and the housing%20,'and.a. hub seal I24 in the partition wall 26, allv shownin. Figure 1.

Gearin component The hub IIII of the runner extends rearwardly through the wall or partition.- 23 into the gearlng chamber25, where it mounts apinionor sun gear I20. l Rotationalsupport. for the; hub

IIlI isprovided by abearing I2I, in-the wallZIi,

and a floating sleeve bearing I22-operatingas a pilot bearing on theiend of the shaft 33, as shown in Figure 6. The impellenand thel runner thereby cooperate in furnishing mutual support and alignment to keep these parts-running true and with the proper relative clearances.

Within the gearing chamber 25 the housing 20 is provided with bearings for a pair of shafts I 26.

carrying-planet gears 121; in meshwith the sun gear I20. Integral with thegears IZ'I-are smaller .gears I28 shown in meshwith a sliding gear I300 135 on shafts I mounted :in'bearings' in the housing 20, so that the gears I35 are constantly in'mesh with the gears I28. The relationship of the various gears isshown in Figures Land 2.

:Manipulation of the rod I33 to shift-gears is effected by a bearing collar Iwhich maybe shifted axially by means of a hand lever I4 I. In

normal forward drive. the gears are maintained in the meshing relationshown in Figure l. To obtain reverse drive the lever 4I' is shifted to its opposite extreme position to mesh the sliding gear I30 with thereversegears I34. Further details of the shifting mechanismwill be hereinafter describedzin connection .vviththe overrunning brake I9. 7

Under-certain conditions,1as when startingthe vehicle engine throughthe rearwheels, it may be desirable tov establishadirectmechanical connection from thedriven shaft, II,to thecrank shaft II). This may readily be accomplished in .the presenttransmission bymovingthe sliding gear I30 to an intermediate. position where it will engage both the forward gears 'I 28 and the reverse gears I34 to lock the shaft I32,to the housing 20, and thenengaging the teeth-6'2 and163 .of the dog clutch I7 tolock the housingZDto the 'shaft'33. In thiscondi'tion. there is no-relative r motion of any of the parts, within the housing 20,

and the whole.- assembly-revolves as a unit with the flywheel I 4.

Fluid pumping system When the'transmission is in operation it is desired that the fluid driving chamber 23 ,be maintained completely, full of c hydraulic fluid undergreater than atmosphericpressure to keep an therefrom, and thatthe gearing chamber 25 contain a reserve supply'of this fluid and make provision for variation in the volume of the fluid.

Figures-5, 6 and 7 disclose a novel pumping system for transferring the hydraulic'fluid from the chamber 25 to the chamber 23, and for maintaining the'desired fluid pressure in the latter cham- L12 :ber. -previously been-pointed-out, the impellerhub-I i is fixedly mounted on the shaft J53-so'asto" rotate therewith, whereas the runner hub -i0I.- rotates onrthe pilot bearing bushing I22 and in the bearing I2I in the wall 25. The arrangement-of theseparts is best shown in Figure 6. The impeller lflis accurately seated in the properaxial position by means of a nut I49 on :the shaft 33. Theextreme end of this shaft is reducedbelow-the threads which hold this nut toturn in relative movement in the bushing I22. Centrally 'containedrwithin these parts is a hollow 'tube'I-50 engaging the inside of an axial bore I5I in the 1 runner hub I0 I in a nonrotative press fit andi-extending rotatively-into an axial bore I52 in theimpellerhub-II to form'an additional bearing to maintain-the-alignment of shaft 33 and the runnerhub IOI. -A bushingor sleeve I53 is interposed between thetube I andthe shaft 33, faiida: thrustwasher I54 is interposed between the "end-ofth'issh'aft andthe runner hub NH. The tube I5 ilv thus constitutes a shaft extending within 'the' shaft 33,:and is provided with an'eccentric -en'd' I55 for'reciprocating apiston I55 in a small ""radial cylinder -I5I extending through thehub II and vthe shaft33. .The piston I56 contains a -'sprin'g;I58: holding it against the eccentric I55. Uponrelative rotation between the tube I50 and the shaft 33,- fiuid is drawn through a passage I00 into-the-space inithe bore, I52-around the eccentric- I 55; and isforced out through an opening I3I 'byreciprocation' of the piston. A ball check valve I52 seatediby'aspr'in'g I 63- prevents leakage of the fluid back through the pumping-system. [he springs I58 and I63 are seated within alp-erforated retaining ring I54; In order to assemble the-runner -I00:on the shaft'33 a ring IE5 is Iplaced inthe'hole 152 beneath the piston I50 to hold 5118113155011 back outofthe hole I52 so that theeccentric I55 maybe inserted beneath the piston. Whengthetube I50 is inserted in the "hole I52"the':eccentric 'I55lpushes the ring I55 ahead of-it until it snaps clear of the piston as shown' in Figure '6. The opening in the ring I55 allows for the entrance offluid from the channel I into the space around the, eccentric.

The outer end of the tube I50 contains a spring I65 seating an intake ball check valve IIi'I in an intake opening I68'inaTflanged plug I69 which hol'dsthe sung'earIZIi on the runner hub IOI.

. Rotatablyamounte'd intheplug I69 is a' T fitting I10 receiving the ends of oppositely extending oil i tubes 'IIIWvh'ose'outer ends are secured closely adjacent .the' wall'of the housing 20 Within the oil reservoir-in*gearingichamber 25. As shown in Figure ,7, theends of the tubes I1 I are secured by clamps" I121t0 lugs I13 at diametrically opposite. pointsion the inside wall of the housing 20.

= Gravity operated ball "check'valves I14 retained bypins I operate to open submerged ends of the tubes HI and to close said ends when they are not-subrnerged. When the housing 20 is sta- .tionary ,or revolving very slowly, the balls will assume:therelative'positions shown in Figure 6 to open the lower end-of the tube and to close the upper end. 51f the chamber 25 is then kept slightly more than half full of fluid, the pumping system-will never run dry. When the housing 20 is rotating with suiflcient speed to distribute the fluid in a; cylindrical ring around the outer wall thereof, both balls I14 will bethrown outwardly by cenrtifugal forcezto admit oil in bothends of the tubes I'II. Relative rotation of the runner I05'with respect to the housing 20 is accommodated by rotation of the plug I69 with respect to communicating with the chamber 25.

13 the fitting I10. This pumping system is designed particularly to avoid a leakage of air through the seal I23 when the fluid in chamber 29 contracts upon cooling. Upon a reduction of fluid pressure in this chamber below atmospheric, the ball check valves I62 and I51 will "readily unseat to draw in fluid from the reservoir in the chamber 25 with-'- out admitting air through the seal I23. It will be observed from Figures and 6 that the pumping chamber is free and open in all positions of the piston I59 and eccentric. I55 to admit fluid through the channel I09 and passage ISI when the parts are at rest. In this connection it is pointed out that there is always 'acertain minimum clearance gap between the eccentric I55 and the inner end of the passage IE! so that this passage will not become closed or obstructed by the eccentric if the parts should come to rest in the position shown in Figure 5. V

Figure 8 discloses a ball check valve I80 to bleed excessive pressures from the chamber 23 back into the chamber 25 to allow for expansion of the fluid under high temperature operating conditions. A plurality of passages -I8I in the wall of the housing 20 establish communication between the chamber 23 and an annular groove I82 leading to a central passage I83 in a plug I 80. The ball I80 is seated against the end of the passage I89 by means of a spring I35, which bottoms in a hole having a reduced opening I86 The spring I85 is of suflicient stiffness to withstand the normal operating pressures developed in the chamber 23, but will yield under excessive fluid pressures to bleed fluid back into the chamber 25 until the excessive pressure is reduced. In the chamber 25 considerable volumetric change is permitted through the provision of a flexible diaphragm I 81 tensioned inwardly by a spring I28 as shown in Figure 1. Suitably located filler and drain plugs such as the plug I89 may be provided in both chambers 23 and 25.

Referring again to Figure 1, it will be seen that the shaft I32 is carried in a sleeve bearin I90 and an oil sealing bearing assembly I9I, both in the end member 59 of the housing 20. The bearing assembly ISI includes clamping" means I92 to seal the diaphragm I81 around the bearing. Within the hollow shaft I32 a suitable packing gland is also provided around the push rod I33 Overrunning clutch,

Referring now to Figure ll, it will be seen that the, push rod I 33 carries a pilot end I95 supported in a sleeve I96 in the shaft I32. A flat pin I91 passes through the rod I33 and is con tained within a slot I98 in the shaft I32 With its ends received in an, inner member I99 of the bearing collar I20. The outer member 200 of the bearing collar M0 isnonrotative, but is arranged to be movedj longitudinally bythe shift lever MI to the extent permitted by the length of the slot I93. The shaft I32, push'rod I33, pin I91, and inner member I99, thereby revolve together as a unitary assembly within the stationary, outer member 200,and the hearing assembly 20I transmits the longitudinal move- .ments of the outer member to the inner memher to shiftthe sliding gear m n the manner previously referred' toQ I Rotation of the outer member 200 is-pr'evented by a plurality of pins 202 slidably'mounted in a cover plate 293-011 the. end of the '-stationary casin'gZI. Thepins 202 are provided with heads 209 and springs 205; and have their inner ends 14 attached to a ring 206 in the overrunning brake mechanism previously referred to generally by the numeral I9.

The construction of the overrunning brake is best shown in Figures 9, 10 and 11. The end member 59 of the housing 20 is rotatable in the bearing GI, and in turn provides a concentric bearing for the shaft I32 as shown in Figure 11. Secured on the member 59 adjacent the bearing SI by means of a nut 20! and a key 208 is a ring 209 having a plurality of oppositely ramped depressions 2I0 containing loose rollers 2I I. Surrounding the ring 209 is a ring or raceway 2I2 locked in the casing 2| by means of the keys 2I3. The ring 2I2 has a smooth cylindrical inner surface of suflicient diameter to clear the rollers 2 when they are centralized in the depressions 2I0, but which will engage and bind the rollers against the ring 209 when they are not centralized in these depressions. The rollers 2II have freedom for radial movement between rings 209 and 2I2 but are each closely confined between a pair of pins 2M extending between rings H5 and 216 and comprising a cage to control the circumferential position of the rollers with respect to the depressions 2I0. 1

Rotational movement of the cage and rollers is controlled by pairs of slots 2I1 and Zlt, receiving pins 220 carried by the ring 209. With the pins 220 extending through the slots 2I9, as shown in Figure 10, the ring 209 is free to rotate a limited distance to the right with respect to the cage, but it cannot move to the left without taking the cage with it. However, a relative movement of the ring 209 within the cage causes the rollers 2 to ride up out of the depressions 2I0 and lock against the outer ring 2I2. The housing 20 which is integral with the ring 209 is, therefore, locked against reverse rotation in the stationary casing 2I which is integral with the outer ring 2I2. It will be observed that movement of the ring 209 and the pins 220 to the right in Figure 10 corresponds to reverse rotation of the housing 20, and that movement of these partsto the left in Figure 10 corresponds to forward rotation of the housing with reference to a conventional clockwise rotating engine crank shaft viewed from thefront end. In other words, when the housing 20 attempts to rotate backwards, the ring 209 and pin 220 move a slight distance to the right in Figure 10 suflicient to raise the rollers 2II into'w'edging engagement with the outer ring 2I2 to prevent any further reverse rotation of the housing 20. On the other hand, the housing 20 is free to rotate in a forward direction because-the pin 229 is already at the left end of the slot H9, and upon moving to the left in Figure 10 there is no relative movement of the ring 209 with respect to the rollers 2II. The rollers ZII are thereby maintained centralized in the depression 2!?) where they cannot bind the rings 209 and 2H2 together in forward movement. To insure relative movement between the ring 209 and the roller cage when the housin 20 tends to rotate in reverse, small frictional elements such as pieces of brake band 22! are mounted on light sprin elements222fbetween certain of the pins 2 III to exert a slight drag on thestationary outer ring 2I2. This drag need be only sufficient to overcome the frictional drag existing between the ring 209 and the'cage. 5 g

. Ithas been stated with reference toFigures 1 and 1-1 that the bearing collar I40 may be moved axially by the reversing lever I0! to move the sliding gear L30; rcarwardly to an; intermedir ate position in engagement with. both; gears. I28 and I34 to lock the housing 2.0. to the. driven shaft; I32. The. length. of the: pins. 282. is such that the member 200 does. not engage the heads functions. as; a. shifter element to withdraw the pins 220. fromthe. short: slots; 218 in-the ring 2J5. Inasmuch as the rollers 21 I. are centralized. in the depressions; 2H1, as shown in. Figure. 9, when the parts are, in. the relative positions shown. in

Figure wherein the pins 226 are. in. the mid portions of, theslots 211,. the withdrawal. of the pins; 22.0 from. the-slots 218 permits slight relative movement in either direction between the ring 209. and. the rollersZIl, the result of which is to. lock the housin .20 to. the nonrotative casing 2|. This locking action is: intended only for. reverse. drive. and, as: has been. stated, not, effected until the reverse gear is substantially fully meshed, The described operation is assured in reverse as: well as in forward. drive by the friction elements 22!. which tend to, hold the rollers -2 I. I, in fixed positions.

When the. reversing lever. IALI is moved; back to forward drive, as shown. in. Figures 1, 10 and 1 1, the pins .202 follow the. member 200 in its movement to the left. as viewed in. Figures 11 and 1-1, until the ends. of the pins 220 strike the ring 216, assuming that the slot 2I.8 is not then in a position to receive the pins. If the impeller is operating, the torque on the housing 29 isv reversed by shifting the sliding gear 36 from the reverse gear I34 to forward. driving gear I28, causing: the ring 209 to move to the right in Figure 10 until the pins 220 are snapped into slots 218 by the action of the springs 26.5. When the member 200 is shifted to forward driving position as shown in Figure 11, the springs 295 are slightly compressed to hold. the pins 220 in the slots 2.I;8. Here again. relative rotation of the ring 2.09 with respect to the ring ZIS to engage the pins 220 in the slots ;2I8 is assured by the action of the friction members 22I as they Operation If the vehicle is not to be driven immediately upon starting the engine, the clutch l6 may be disengaged to warm up the engine. When the vehicle is to be started in forward drive, the lever I 4| should bev in position to engage the sliding gear I30 with the gears I28, and the dog clutch I! should be disengaged, as shown in Figure 1. When the clutch I6 is engaged, the impeller it? will rotate in. a. clockwise direction as indicated by the arrow in Figures 3 and 4. With the engine operating; at idling speed, the hydraulic fluid in the chamber 23 iscirculated through thevarious vanes atrelatively low velocity so that a relatively small torque is transmitted to the shaft I32. and. driven shaftv I I. When the engine is accelerated, thehydraulic fluid is discharged in streams moving at high velocity through the. impeller passages. H0. and. split in across the, diagonal reaction vanes 82. in a: on pulsatin even. flows. The circular motion of; the fluid produces. a forward torque. on the vanes {32, tending: to. rotate the; housing 26 in a forward direction as,v indicated. by the arrow 225 in- Figure. 3, but. this torque is opposed by the superior reaction. torquesv ofthe vanes 83' and the planet gears I21, so: that. the resultant torque on the housing 20 is. in. a, reverse direction causing the housing to: be; held stationary during this phase of operationzby the. overrunning brake I9. When the. reaction vanes: .82. are stationarm. they function merely as guide vanes. to direct the fluid flow in. a. forward or; clockwise direction in the annular passage I.l:3., as, indicated by the, arrow 225.; In the. passage. M3 the fluid revolves in a circular direction at high velocity and. moves radially wardly untilit is. rotating on. the same radius as the runner vanes H15. The fluid. then moves. into. the runnervanes in; a. helical path havingciroumferential. and axial velocity com,- ponents: as. indicated by: the arrows 221:. When the runner vanes; i053 are moving at a low speed relative. to; the fluidvelocity; the rotational movementof thefluidwilljbereversed by the. bucket surfaces. I01 so: astoemerge. in the direction. of thearrow- I I 4. in Figure. 3; and rotate in the. chamber; II .5. in a, backward, direction. In. changing its. direction. from clockwise. to. counterclockwise rotation, the. reaction of the. high velocityxfluid exerts; a; driving; force. on. the. vanes I which develops: a forward. torque in. the runner hub I .0 II to drive: the gear I30 through the ears I20, 21; andv 1.2.8 in. the. now stationary housin the torque; multiplication in: the gearing c mponent under this condition beingapproximately two to; one. i

In the annular passage lit: the. fluid moves radially inwardly to. a smaller radius of; rotation inv a position to enter the reaction vanes 8.3. with circumferential and axial velocity components as. shown by the. arrows. 2.29:. In passing through these vanes. thefluidv exerts a reverse or counterclockwise torque which is added to the counterclockwise. reaction. of the gears I21 and I28 and which is resisted in the manner previously mentioned by the externalv abutment provided in the cverrunningbrake I9;

From the vanes 83. the fluid is discharged with a counterclockwise rotation, as indicated. by the arrows I I6 and 231], for circular movement in the last annular passage 103. The fluid spiral tightens in this passage to the, diameter of the eye opening 85 andmoves therethrough and into the eye of the impeller in. av counterclockwise helical path, asindicated by the arrows T6 in Figure 4. The large vanes 15 of the impeller are inclined. backwardly to providev an. easy entrance to reverse rotating. fluid to avoid shock and energy losses. underthis condition of operation,

7 and to increase the radial flowv through the impeller which produces a high velocity of fluid H flow. The. practical result accomplished by this construction and. mode f Operation is rapid accolorationv of the fluid now in starting which producesa more. rapid acceleration of the vehicle from a standing start than can be obtained in conventional fluidd-riving transmissions. In the impeller the high velocity radial flow has imparter thereto a clockwise. rotation ending in a substantial tangential thrust by the curved. blade endsv I 8 which add a tangential component to the radial velocity component. In this way, it is believed that the power output of the engine is utilized to the best advantage to most rapidlyaccelei'ate the hydraulic fluid to the high velocity necessary for'high starting torque. The advantage of high starting torque is,v of course, not limited to vehicular-applications as it isdesirable in power transmissionsfor all purposes, and it is not intended to limit thepresen't transmission to any particular use; v

The interposition-of the small vanes 14 between the outerends of the large vanes '13 increases the l efficiency and discharge of the impeller by preve'ntinglocal return flow or eddies behind the tips-of-the large vanes.

It is to be emphasized that the predominant direction of fluid flowin the passage H at the outlet of the turbine runner is in acircular dimotion, and that at low-runner speeds-the axial component of the fluid velocity is relatively small. Furthermore, the width of the passage I IS in an axial direction is relativelyfsmall so as to cause thewall'8B to deflect-fluid leaving the runner in the direction oi the arrow H4 in-Figure'B immediately into' a circular path as indicated by the arrow 228. If "the wall88fwere notpresent, the arrow H4 would gradually -change' 'its direction with higher runner 'speeds until it had shifted to the new position indicated by the broken arrow- IM. The-passage 115, however, does not allow space for a gradual change in the 1 direction of fiow of the liquid therein,'since the flow is constrained to a circular'path where it must travel either in' one direction or the other. 'I'hereforaas the speed of the'runner increases, the fluid circulation in the passage 1 I5 will continue-in the direction indicated by the arrow 228 until the arrow l I4, considered as a velocity vector immediatelyfat the edges of, the vanes I05,'shifts past the perpendicular, and then the entire circular flow in the passage H5 must reverse abruptly to -the direction indicated by the broken arrow 22B. c

In its new direction-of rotation, the yelocity components of fluid about to enter thej vanes 83 are indicated by the arrows 229'; This; direction of flow directs the fluid against the concave sides 9! of the vanes 83, 'exerting a clockwise or forward torque on-thereaction members!) in ad:- dition to the forward torque exerted upon the vanes 82, and the partsareproportioned and designed so that thesum of these two forward torques is superior to the counterclockwise reactiontorque exerted by the gears i21 and i28. When the runner has 'attaineda certain speed, the housing 20, therefore, leaves the abutment provided by the overrunning brake l9, and be? gins to rotate in a'forwarddirection but at a slower speed than the runner; 1 The power flow which had been diverted exclusively through the runner While the housing was stationary is nowdivided between two paths comprising the runner and the reaction, member, or housing, to produce amultiplication"offtorque in the 'flu iddriving component in addition to the torque multiplication in (the gearing component. Inthe gearing component, also, the power flow is divided' in two paths comprising the sun gear I20 andthe revolving housing 20 operating as-a planet carrier. When thehousing revolves,- the vanes 82 and 83tmay. be considered asop'erating as a combination:fluidJcOupIing "and torque' c'o'm vertertransmitting torque to: the gearin'gi com ponent in parallel with the runner with" whichiit then shares the load. Thus the torque'output of the reaction member, or housing is then added to that "of the turbine runner tomaintain a high torque multiplication in the fluid driving component in intermediate operating speeds. As the speed of the runner increases, the speedof the housing tends to increase also, with the result of efiecting a higherspeed transmission ratio, which is desired as the vehicle or other machine operated by the transmission gets into motion.

When the housing isrevoliilng slowly relative to the speed of the fluid circulation, the discharge from the vanes 83 will be in the direction of the previously mentioned arrow 7 H6 to produce a counterclockwise circulation in the passage Hi3, as indicated by thearrow 230. As the speed of the housing increaseathe direction of the arrow H6, considered as a velocity vector for liquid leaving the tips of thevanes 83, would tend to slowly shift to thepositionv shown by the broken arrow H6 but the direction of circulation of the mass of liquid inthe passage I03 is prevented by the adjacent confining wall I02 from changing gradually from theposition of the arrow 230 to the arrow 230. Therefora'at .a certain critical speed of the housingrelative: to the fluid velocity, the fluid circulation in the passage [03 will abruptly change and flow in the forward direction indicated by the broken line arrow 230;

Fluid circulating in this direction passes through the eye'opening 85 in a clockwise spiral and enters the eye of the impeller in the direction indicated by the brokenline arrows H in Figure 4. By maintaining a uniform velocity in a closed circuit the-rotational velocity of the returning fluid will be substantially equal to that of the fluid leaving the impeller. Inasmuch as the inner endslof vanes 13 rotateat about half the linear speed of the outer endsthefluidentering the eye of the impeller impinges against the back sides of these varies on curved surfaces 19'to produce an additional force;:over-th'at' of thejnputpower to help drivethe impelle'rljAs the fluid moves out through the vanes 13; and 14; it is again discharged with radial and tangential velocity. componentsv into the moving vanes" 82 which then function both as guide vanesand-additionally as a fluid coupling, runner inithe manner described. 7 Thus it is seen that'a compound torque multiplication is achieved in the, two components of the present transmission substantially throughout its operating range by providing, two paths of power flow, through interconnected elements in the two components. Thepresent transmission obtains an unusually-high torque multiplication in the fluid driving component-by maintaining the hydraulic fluid in circular movement between a succession of working stages and by utilizing reaction forces from'reversals ofthis circular movement to develop torque in the working stage without arresting the circular motion of the fluid.

Having now; described my invention, and. in what manner the same may be used, whatrI claim as new and desire to protect'by Letters Patent is:

'l-JIn a power transmission, 'an impeller and a plurality of fluid driven members in afiuid circuit, sets of axial 'flowvanes on said members-' 'at'dif fere'nt radial distances from' a common. axis'i'ot rotation, the outermostset of vanes receiving' the discharge from'sa'id impeller, means at the discharge side of each set of vanes exceptthe innermost set to reverse the direction of 'axialflow into the next radially inwardsetoffvanes; and means at the discharge side of the; innermost sfet of vanes to reverse -'the direction-of axial flow and return the flow to the eye-of theimp'ellers f .:2..In a power transmission, an impeller anda lurality .of sets :of vanes constituting-working 19 stages in a return fluid circuit to the eye of the impeller, and annular passages at opposite ends of said stages for directing hydraulic fluid from said impeller back and'forth in. opposite axial directions through said working stages in succession before the fluid is returned to the impeller.

3. In a power transmission, a rotary fluid impeller and a plurality of coaxial bladed wheels in a fluid circuit, said bladed wheels constituting successive axial flow working stages for the transmission of torque from said impeller, means at the discharge side of each stage before the last stage to reverse the direction of axial flow into the next stage, and means at the discharge side of the last stage to reverse the direction of axial flow and return it to the eye of the impeller.

l. In a power transmission, an impeller having a radial discharge, a reaction member having a first set of. vanes surrounding. said impeller and directing said radial discharge in an axial flow, a runner concentric with said. first set of vanes and receiving thedischarge therefrom in a reverse axial flow, a secondset of vanes on said reaction member concentric within said runner vanes and receiving the discharge therefrom in the direction of said first axial flow, and means for completing the fluid circuit in a reverse axial flow within said second set of vanes back to the eye of the impeller. V

5. .In a power transmission, a fluid torque converter comprising an impe1ler, a reaction member and an axial flow runner in a fluid circuit, said impeller having a radial discharge, said reaction member having diagonal guide vanes portions of which 'surroundsaid impeller and receive the a output therefrom, an axial flow runner concentric within other portions of said guide vanes, and a set of. axial flow vanes 'on said reaction member concentric within. said runner.

6. In a power transmission, a torque converter comprising a radial flow impeller, a reaction member having an axial flow first stage a portion of which surroundssaid impeller, an axial flow runner within another portion of said first stage, said reaction member having a second axial flow stage within said runner, and meansfor mounting said reaction memberfor rotation to produce a driving torque- I V I 7. In a power transmission, an impeller, a plurality of fluid driven members mounted for rotation about a common. axis, sets of axial flow vanes 7 the other in concentric relation, and a fluid driving circuit for guiding hydraulic fluid axially through said sets of vanes in opposite axial directions in successive working stages and radially between said sets of vanes before the fluid is returned to the impeller.-

9. In a power transmission, an impeller, a plurality of rotary fluid drivenmembers of diiferent diameters nested together in concentric relation each having vanes for guiding hydraulic fluid axially therethrough at a constant radius of rotation, and annular chambers on opposite 20' sides of said members for-moving the fluid flow radially from each of said members to the next inner member and for reversing the axial direction of flow at the entrance to each driven memher, before the fluid is returned tothe impeller.

10. In a power transmission device, a reaction member having a first set, of vanes confined between inner and outer cylindrical shells, a runner concentric within said first set of vanes and having vanes. confined between inner and outer cylindrical shells, and a second set of vanes on said reaction member confined between inner and outer shells concentric within said runner vanes. j

11; In apower transmission device, an impeller, a reactionmember having a first set of vanes'conflned between outer and inner cylindrical shell members, a runner within said first set of vanes havingvanes confined between inner and outercylindrical shells, and a second set of vanes-on said reaction member within said runner and. confined between inner and outer shells, said last mentioned inner shell having a diameter corresponding'to the diameter of the eye of the impeller.

12.'In a power transmission, a fluid impeller having a radial discharge, a reaction member having a first set of vanessurrounding said impeller and receiving the discharge therefrom, a cylindrical wall inside said first set of vanes, a runner concentric within said cylindrical wall and receiving the discharge from said first set of vanes, a cylindricial wall within said runner, a second set of vanes on said reaction member concentricwith'in said runner, a cylindrical wall within said second set of vanes, and annular passages forming a fluid circuit around the ends of said walls to define a fluid circuit back to the eye of said impeller. v

13.. In a power transmission, an impeller arranged to pump hydraulic fluid through a working circuit to transmit torque from a driving shaft to a driven shaft, a plurality of sets of vanes in said circuit acted upon by said fluid in axial flow, and means for reversing the direction of axial flow in each successive set of vanes before thefluid is returned to the impeller, all the vanes in said working circuit being capable of exerting a drivingtorque on said driven shaft.

14. In a power transmission, an impeller having a radial discharge, a rotatably mounted reaction member having a first set of vanes surrounding said impeller to receive the output therefrom and direct it in axial flow, said first set of vanes being disposed diagonally with the axis of said impeller, a runner receiving the discharge from said first set of vanes in reverse axial flow, and a second set of vanes on said reaction member receiving the discharge from said runner in the direction of said first axial flow.

15. A power transmission comprising a housingmounted for rotation, a partition in said housing forming fluid driving and gearing chambers therein, said gearing'chamber constituting a reservoir for hydraulic fluid, a pump between said chambers having aninlet in said gearing chamber and an'outlet in said fluid driving chamber for pumping fluid from said reservoir into said fluid driving chamber, means for operatively connecting the. inlet for said pumpwith the body of fluid in said reservoir regardless of whether said housing is revolving orstationary, and a direct passage through said inlet and said pump" capable of conveying fluid from said reservoir to said fluid driving chamber when the pressure into both of said chambers, pump means in said member for pumping hydraulic fluid from said gearing chamber to said fluid driving chamber, a pair of inlets for said pump means on diametrically opposite sides of the internal periphery of said gearing chamber, and valve means in said inlets responsive to gravity to close the uppermost inlet and open the lowermost inlet when the housing is stationary or revolving slowly and responsive to centrifugal force to open both inlets when the housing isrevolving rapidly in order to open the submerged inlets and close the emerged inlets under all operating and nonoperatlng conditions of said transmission.

17. In a power transmission, a rotatably mounted housing comprising a fluid driving chamber and a gearing chamber, impeller and runner members mounted for independent rotation in said fluid driving chamber and said runner member extending into said gearing chamber, pump means in said runner member for pumping hydraulic fluid from said gearing chamber into said fluid driving chamber, means for operating said pump by the relative rotation of said impeller and runner members, and means in said runner member to prevent the return of fluid back through said pump to said gearing chamber.

13. In an hydraulic transmission, an impeller adapted to receive a fluid intake in either forward or counter rotating flow, said impeller having blades with concave rear surfaces near their inlet ends to utilize the kinetic energy of said forward rotating flow to assist in driving said impeller, said blades being backwardly inclined to receive a counter rotating flow without shock and change said flow into radial flow utilizing the initial counter rotational velocity to produce additional radial velocity, and forwardlycurved outlet ends on said blades to throw the fluid tangentially as it leaves the impeller to add a 21. In a power transmission, a fluid impeller having radial flow blades, a rotatable reaction member having means to prevent reverse rotation, a first set of axial flow blades on said reaction member receiving the discharge from said impeller, a runner having a set of curved axial flow blades receiving a tangential discharge from said first set of reaction member blades and shaped to reverse the tangential direction of said discharge when the speed of the runner is relatively slower than the velocity of fluid flow, a second set of axial flow blades on said reaction member, and an annular channel concentric with the axis of said reaction member in the fluid circuit between said runner blades and said second set of reaction member blades to constrain the tangential discharge from said runner blades to flow to said second set of reaction member blades in a circular path in said channel.

22. In a fluid power transmission, an impeller having'radial flow blades and an axial fiow input eye, a reaction member mounted for rotatangential velocity component to the radial velocity component.

19. In an hydraulic transmission, an impeller having backwardly inclined blades with refer ence to the direction of rotation, concave rear surfaces near the inlet ends of the blades, forwardly curved outlet ends on said blades, and short blades between said blades to prevent return circulation and eddies behind said outlet ends of said blades.

nel at the discharge side of said guide vanes to direct the fluid flow axially into said runner, said guide vanes being arranged diagonally across each throat of said impeller to divide the fluid flow from each said throat over two or more vanes to avoid-power impulses.

tion in the direction of said impeller and having means to prevent reverse rotation, a first set of blades on said reaction member surrounding said impeller and directing the discharge from the impeller in an axial direction, a turbine runner at one side of said impeller having axial flow blades concentric within said first set of reaction blades, said reaction member having a smooth curved wall defining an annular channel I communicating with the discharge side of said REFERENCES CITED The following references are of record in the file of this patent:

Number Name Date UNITED STATES PATENTS 1,199,360 Fottinger Sept. 26, 1916 1,304,566 Hornbrook May 27, 1919 1,327,080 Brown Jan, 6, 1920 1,600,626 Ford Sept. 21, 1926 1,696,307 James Dec. 25, 1928 1,855,967 Jandasek Apr. 26, 1932 1,857,252 Miller May 10, 1932 1,859,607 Sinclair May 24, 1932 2,015,300 Dell Sept. 24, 1935 2,021,574 Cottrell Nov. 19, 1935 2,055,895 Fawcett Sept. 29, 1936 2,129,884 Swan Sept. '13, 1938 2,146,369 Dodge Feb. 7, 1939 2,149,117 Dodge Feb. 28, 1939 2,235,370 Jandasek Mar. 18, 1941 2,240,650 Heyer May '6, 1941 2,276,695 Lavarello Mar. 17, 1942 2,293,767 Salerni Aug. 25, 1942 2,316,390 Biermann Apr. 13, 1943 2,397,869 Kirby Apr. 2, 1946 

